Question

A crate resting on a horizontal floor (\muμs = 0.61, \muμk = 0.3 ) has a horizontal force F = 49 Newtons applied to the right. This applied force is the maximum possible force for which the crate does not begin to slide. If you applied this same force after the crate is already sliding, what would be the resulting acceleration (in meters/second2) ?

Answer 1

Answer:

a = 7.80 m/s²

Explanation:

given,

μs = 0.61

μk = 0.3

F = 49 N

we know,

F = μs m g

$m = \dfrac{F}{\mu_s\ g}$

$m = \dfrac{49}{0.61 \times 9.81}$

$m = 8.19\ kg$

now when the block start moving

$F - F_k = F_{net}$

$F - F_k = ma$

$a = \dfrac{F}{m}-\dfrac{F_k}{m}$

$a = \dfrac{F}{m}-\dfrac{\mu_k m g}{m}$

$a = \dfrac{88}{8.19}-0.3\times 9.8$

a = 7.80 m/s²